debugger

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

Thedebugger statement invokes any available debuggingfunctionality, such as setting a breakpoint. If no debugging functionality is available,this statement has no effect.

Syntax

debugger;

Examples

Using the debugger statement

The following example shows code where adebugger statement has beeninserted, to invoke a debugger (if one exists) when the function is called.

function potentiallyBuggyCode() {  debugger;  // do potentially buggy stuff to examine, step through, etc.}

When the debugger is invoked, execution is paused at thedebuggerstatement. It is like a breakpoint in the script source.

A browser with developer tools open to the debugger panel showing how execution is paused at the debugger statement to allow close inspection of variables, scopes, events, etc.